AP meaning in Computer Hardware ?

The use of energy is considered sustainable if it "meets the needs of the present without compromising the ability of future generations to meet their own needs". There are many definitions of sustainable energy. Most include environmental aspects such as greenhouse gas emissions and social and economic aspects such as energy poverty. Renewable energy sources such as wind, hydroelectric power, solar, and geothermal energy are generally far more sustainable than fossil fuel sources. However, some renewable energy projects, such as the clearing of forests to produce biofuels, can cause severe environmental damage. The role of non-renewable energy sources has been controversial. Nuclear power is a low-carbon source whose historic mortality rates are comparable to wind and solar, but its sustainability has been debated because of concerns about radioactive waste, nuclear proliferation, and accidents. Switching from coal to natural gas has environmental benefits, including a lower climate impact, but may lead to a delay in switching to more sustainable options. Carbon capture and storage can be built into power plants to remove their CO
2 emissions, but is expensive and has seldom been implemented.

Eighty-five percent of the world's energy is derived from fossil fuels and the global energy system is responsible for 76% of the human-caused greenhouse gas emissions that cause climate change. Around 790 million people in developing countries lack access to electricity and 2.6 billion rely on polluting fuels such as wood or charcoal to cook. Reducing greenhouse gas emissions to levels consistent with the 2015 Paris Agreement will require a system-wide transformation of the way energy is produced, distributed, stored, and consumed. The burning of fossil fuels and biomass is a major contributor to air pollution, which causes an estimated 7 million deaths each year. Therefore, the transition to a low-carbon energy system would have strong co-benefits for human health. Pathways exist to provide universal access to electricity and clean cooking in ways that are compatible with climate goals, while bringing major health and economic benefits to developing countries.

Climate change mitigation scenarios describe pathways in which the world would shift to low-emission methods of generating electricity, rely less on burning fuels for energy, and rely more on electricity instead. For some energy-intensive technologies and processes that are difficult to electrify, many scenarios describe a growing role for hydrogen fuel produced from low-emission energy sources. To accommodate larger shares of variable renewable energy, electrical grids require flexibility through infrastructure such as energy storage. To make deep reductions in emissions, infrastructure and technologies that use energy, such as buildings and transport systems, would need to be changed to use clean forms of energy and also to conserve energy. Some critical technologies for eliminating energy-related greenhouse gas emissions are not yet mature.

Wind and solar energy generated 8.5% of worldwide electricity in 2019. This share has grown rapidly while costs have fallen and are projected to continue falling. The IPCC estimates that 2.5% of world GDP would need to be invested in the energy system each year between 2016 and 2035 to limit global warming to 1.5 °C (2.7 °F). Well-designed government policies that promote energy system transformation can lower greenhouse gas emissions and improve air quality. In many cases they also increase energy security. Policy approaches include carbon pricing, renewable portfolio standards, phase-outs of fossil fuel subsidies, and the development of infrastructure to support electrification and sustainable transport. Funding research, development, and demonstration of new clean energy technologies is also important.